Target Searches of Interacting Brownian Particles

We study the target search of interacting Brownian particles in a finite domain, focusing on the effect of inter-particle interactions on the search time. We derive the integral equation for the mean first-passage time and acquire its solution as a series expansion in the orders of the Mayer function. For dilute systems relevant to most target search problems, we analytically obtain the leading order correction to the search time and prove a universal relation given by the particle density and the second virial coefficient. Finally, we validate our theoretical prediction by Langevin dynamics simulations for the various types of the interaction potential

The Effects of Flow on Learning Outcomes in an Online Information Management Cou

As online courses and programs expand in business schools, it becomes increasingly important to understand the link between students\u27 experiences in these courses and learning outcomes. The study reported here investigates the relationship between students\u27 experiences of flow, a psychological state generally associated with improved task performance, and learning outcomes in an online information management course taught in an MBA program. Four learning outcomes (objective learning performance, perceived learning of the subject matter, perceived skill development, and student satisfaction) are predicted to be affected by an overall flow score, four dimensions of flow, and three characteristics of flow activities. Support is found for a relationship between flow and students\u27 perceived learning of the subject matter, students\u27 perceived skill development, and student satisfaction. The findings of the study have implications for the design and instruction of online courses offered in business schools

Indomethacin protects rats from neuronal damage induced by traumatic brain injury and suppresses hippocampal IL-1β release through the inhibition of Nogo-A expression

BACKGROUND: Nogo-A is a member of the reticulon family of membrane-associated proteins and plays an important role in axonal remodeling. The present study aimed to investigate alterations in Nogo-A expression following traumatic brain injury (TBI)-induced inflammation and neuronal damage. METHODS: A weight-drop device was used to deliver a standard traumatic impact to rats. Western blot, RT-PCR and ELISA were used to analyze the expression of Nogo-A and IL-1β. Nogo-A antisense, and an irrelevant control oligonucleotide was intracerebroventricularly infused. We also performed H & E staining and luxol fast blue staining to evaluate the neuronal damage and demyelination resulting from TBI and various treatments. RESULTS: Based on RT-PCR and western blot analyses, the expression of Nogo-A was found to be significantly upregulated in the hippocampus beginning eight hours after TBI. In addition, TBI caused an apparent elevation in IL-1β levels and severe neuronal damage and demyelination in the tested animals. All of the TBI-associated molecular and cellular consequences could be effectively reversed by treating the animals with the anti-inflammatory drug indomethacin. More importantly, the TBI-associated stimulation in the levels of both Nogo-A and IL-1β could be effectively inhibited by a specific Nogo-A antisense oligonucleotide. CONCLUSIONS: Our findings suggest that the suppression of Nogo-A expression appears to be an early response conferred by indomethacin, which then leads to decreases in the levels of IL-1β and TBI-induced neuron damage

Unveiling the nature of the "Green Pea" galaxies

We review recent results on the oxygen and nitrogen chemical abundances in extremely compact, low-mass starburst galaxies at redshifts between 0.1-0.3 recently named to as "Green Pea" galaxies. These galaxies are genuine metal-poor galaxies ($\sim$ one fifth solar) with N/O ratios unusually high for galaxies of the same metallicity. In combination with their known general properties, i.e., size, stellar mass and star-formation rate, these findings suggest that these objects could be experiencing a short and extreme phase in their evolution. The possible action of both recent and massive inflow of gas, as well as stellar feedback mechanisms are discussed here as main drivers of the starburst activity and their oxygen and nitrogen abundances.Comment: To appear in JENAM Symposium "Dwarf Galaxies: Keys to Galaxy Formation and Evolution", P. Papaderos, G. Hensler, S. Recchi (eds.). Lisbon, September 2010, Springer Verlag, in pres

A vacuum ultraviolet ion source (VUV-IS) for iodide-chemical ionization mass spectrometry: a substitute for radioactive ion sources

A&nbsp;new ion source (IS) utilizing vacuum ultraviolet (VUV) light is developed and characterized for use with iodide&ndash;chemical ionization mass spectrometers (I&minus;-CIMS). The VUV-IS utilizes a&nbsp;compact krypton lamp that emits light at two wavelengths corresponding to energies of &sim;10.030 and 10.641&thinsp;eV. The VUV light photoionizes either methyl iodide (ionization potential, IP&thinsp;=&thinsp;9.54&thinsp;&plusmn;&thinsp;0.02&thinsp;eV) or benzene (IP&thinsp;=&thinsp;9.24378&thinsp;&plusmn;&thinsp;0.00007&thinsp;eV) to form cations and photoelectrons. The electrons react with methyl iodide to form I&minus;, which serves as the reagent ion for the CIMS. The VUV-IS is characterized by measuring the sensitivity of a&nbsp;quadrupole CIMS (Q-CIMS) to formic acid, molecular chlorine, and nitryl chloride under a&nbsp;variety of flow and pressure conditions. The sensitivity of the Q-CIMS, with the VUV-IS, reached up to &sim;700&thinsp;Hz&thinsp;pptv&minus;1, with detection limits of less than 1&thinsp;pptv for a&nbsp;1&thinsp;min integration period. The reliability of the Q-CIMS with a&nbsp;VUV-IS is demonstrated with data from a&nbsp;month-long ground-based field campaign. The VUV-IS is further tested by operation on a&nbsp;high-resolution time-of-flight CIMS (TOF-CIMS). Sensitivities greater than 25&thinsp;Hz&thinsp;pptv&minus;1 were obtained for formic acid and molecular chlorine, which were similar to that obtained with a&nbsp;radioactive source. In addition, the mass spectra from sampling ambient air was cleaner with the VUV-IS on the TOF-CIMS compared to measurements using a&nbsp;radioactive source. These results demonstrate that the VUV lamp is a&nbsp;viable substitute for radioactive ion sources on I&minus;-CIMS systems for most applications. In addition, initial tests demonstrate that the VUV-IS can be extended to other reagent ions by the use of VUV absorbers with low IPs to serve as a&nbsp;source of photoelectrons for high IP electron attachers, such as SF&minus;6</p

EFEMP1 suppresses malignant glioma growth and exerts its action within the tumor extracellular compartment

<p>Abstract</p> <p>Purpose</p> <p>There are conflicting reports regarding the function of EFEMP1 in different cancer types. In this study, we sought to evaluate the role of EFEMP1 in malignant glioma biology.</p> <p>Experimental Design</p> <p>Real-time qRT-PCR was used to quantify <it>EFEMP1 </it>expression in 95 glioblastoma multiforme (GBM). Human high-grade glioma cell lines and primary cultures were engineered to express ectopic EFEMP1, a small hairpin RNA of EFEMP1, or treated with exogenous recombinant EFEMP1 protein. Following treatment, growth was assayed both <it>in vitro </it>and <it>in vivo </it>(subcutaneous (s.c.) and intracranial (i.c.) xenograft model systems).</p> <p>Results</p> <p>Cox regression revealed that EFEMP1 is a favorable prognostic marker for patients with GBM. Over-expression of EFEMP1 eliminated tumor development and suppressed angiogenesis, cell proliferation, and VEGFA expression, while the converse was true with knock-down of endogenous EFEMP1 expression. The EFEMP1 suppression of tumor onset time was nearly restored by ectopic VEGFA expression; however, overall tumor growth rate remained suppressed. This suggested that inhibition of angiogenesis was only partly responsible for EFEMP1's impact on glioma development. In glioma cells that were treated by exogenous EFEMP1 protein or over-expressed endogenous EFEMP1, the EGFR level was reduced and AKT signaling activity attenuated. Mixing of EFEMP1 protein with cells prior to s.c. and i.c. implantations or injection of the protein around the established s.c. xenografts, both significantly suppressed tumorigenicity.</p> <p>Conclusions</p> <p>Overall, our data reveals that EEFEMP1 suppresses glioma growth <it>in vivo</it>, both by modulating the tumor extracellular microenvironment and by altering critical intracellular oncogenic signaling pathways.</p

Exercise-induced bronchoconstriction and atopy in Tunisian athletes

<p>Abstract</p> <p>Background</p> <p>This study is a cross sectional analysis, aiming to evaluate if atopy is as a risk factor for exercise induced bronchoconstriction (EIB) among Tunisian athletes.</p> <p>Methods</p> <p>Atopy was defined by a skin prick test result and EIB was defined as a decrease of at least 15% in forced expiratory volume in one second (FEV1) after 8-min running at 80–85% HRmaxTheo. The study population was composed of 326 athletes (age: 20.8 ± 2.7 yrs – mean ± SD; 138 women and 188 men) of whom 107 were elite athletes.</p> <p>Results</p> <p>Atopy was found in 26.9% (88/326) of the athletes. Post exercise spirometry revealed the presence of EIB in 9.8% of the athletes including 13% of the elite athletes. Frequency of atopy in athletes with EIB was significantly higher than in athletes without EIB [62.5% vs 23.1%, respectively].</p> <p>Conclusion</p> <p>This study showed that atopic Tunisian athletes presented a higher risk of developing exercise induced bronchoconstriction than non-atopic athletes.</p

The Wnt Transcriptional Switch: TLE Removal or Inactivation?

Peer Reviewedhttps://deepblue.lib.umich.edu/bitstream/2027.42/141086/1/bies201700162.pdfhttps://deepblue.lib.umich.edu/bitstream/2027.42/141086/2/bies201700162_am.pd

A clinical evaluation of amlexanox oral adhesive pellicles in the treatment of recurrent aphthous stomatitis and comparison with amlexanox oral tablets: a randomized, placebo controlled, blinded, multicenter clinical trial

<p>Abstract</p> <p>Background</p> <p>Amlexanox has been developed as a 5 percent topical oral paste for the treatment of patients with recurrent aphthous stomatitis (RAS) in most European countries. However, it is not yet available in China and has not been generally accepted in clinical treatment. The aim of this study was to explore the effectiveness of amlexanox oral adhesive pellicles in the treatment of minor recurrent aphthous ulcers, and compare the results with those of amlexanox oral adhesive tablets in order to analyse the difference between the two dosage forms of amlexanox.</p> <p>Methods</p> <p>We performed a randomized, blinded, placebo-controlled, parallel, multicenter clinical study. A total of 216 patients with minor recurrent aphthous ulcers (MiRAU) were recruited and randomized to amlexanox pellicles or placebo pellicles. Pellicles were consecutively applied four times per day, for five days. The size and pain level of ulcers were measured and recorded on treatment days 0, 4 and 6. Finally, the results were compared with those of our previous 104 cases treated with amlexanox tablets.</p> <p>Results</p> <p>Amlexanox oral adhesive pellicles significantly reduced ulcer size (P= 0.017 for day 4, P=0.038 for day 6) and alleviated ulcer pain (P=0.021 for day 4, P=0.036 for day 6). No significant difference was observed in the treatment effectiveness between the pellicle and tablet form of amlexanox.</p> <p>Conclusions</p> <p>Amlexanox oral adhesive pellicles are as effective and safe as amlexanox oral adhesive tablets in the treatment of MiRAU for this Chinese cohort. However, pellicles seem to be more comfortable to use when compared with the dosage form of tablets. Therefore, in clinical practice, amlexanox oral adhesive pellicles may be a better choice for RAS patients.</p> <p>Trials registration</p> <p>Nederlands Trial Register NTR1727.</p